The present invention relates to devices which control the pivoting relationship between two adjoining members, and in particular, to devices having two members rotationally pivotal one with respect to the other and having a fluid as an operating medium to provide the control function.
Pivotal or rotational control devices for use as dampers to control the rotational rate of one member with respect to another are well-known in the art. Rotational dampers typical comprise an outer stator and an internal rotor which define between them a chamber filled with fluid. Blades disposed substantially radially on each of the stator and rotor divide the internal chamber into one or more smaller chambers, each rotor blade being rotatable about a central axis of the rotor and angularly limited in travel between adjacent fixed stator blades. These dampers also provide for the restricted flow of the internal fluid between adjacent subcavities as the rotor rotates within the stator. The restricted flow of the fluid between chambers providing the desired damping action.
These dampers are typically used in vehicle suspension systems wherein the stator is generally affixed to the vehicle chassis and the rotor is mechanically linked to a vehicle wheel via an arm of the suspension such that as the vehicle encounters a bump, the vertical movement of the wheel is translated by connecting linkage into a pivotal rotation of the damper rotor.
Similarly, hydraulic motors or pivotal actuators also incorporate an external stator and an internal rotor wherein each has one or more radial blades attached thereto. When functioning as an actuator, the actuator is hydraulically connected to an outside source which provides pressurized hydraulic fluid to the interior cavity of the actuator. As pressurized hydraulic fluid is introduced into one of the subchambers, the rotor is induced to rotate within the stator as an equal volume of hydraulic fluid is permitted to exit from the opposite side of the chamber in which the rotor blade is rotating.
The use of such pivotal control devices has found wide spread use in the construction and manufacture of vehicle suspension systems and in other applications. Heretofore, each desired pivotal control function has been typically administered by the addition of separate axial control devices. The incorporating of separate devices for each control function have certain drawbacks and disadvantages, particularly with respect to the cost and space constraints of incorporating separate devices within one functional mechanism.